In Typescript, is there a specific type for images encoded in base64 format?

As a newbie to Typescript, I am diligently typing everything precisely as part of my learning journey.

A property called lqip (low quality image placeholder) is being pulled from a CMS and should be a base64 encoded image. It's clearly a string, but it doesn't quite feel accurate to just type it as a string.

mainImage: Schema.Post["mainImage"] & {
  // 🤔 can I be more precise? It should always be a base64 encoded image, not just any generic string…
  // e.g. "data:image/jpeg;base64,/9j/2wBDAAYEB…"
  lqip: string
}

Is there a specific data type for base64 encoded images in Typescript? My extensive Google searches only turned up information on atob/btoa conversions, rather than the type itself. Thank you!

typescriptbase64typescript-typings

Answer â„–1

For those who are in search of a solution, consider crafting your own custom type

type Base64<imageType extends string> = `data:image/${imageType};base64${string}`

const base64: Base64<'png'> = 'data:image/png;base64test...'

Feel free to experiment here

Answer â„–2

There may not be a built-in type for this, however, you have the option to define your own custom type that serves as an alias for a string type. By doing so, you can clearly differentiate between a standard string and your specialized base type when examining your code.

type Base64 = string
mainImage: Schema.Post["mainImage"] & {
  lqip: Base64
}

Answer â„–3

Utilizing opaque types can provide an added layer of security in this scenario; although TypeScript does not inherently support them, it is feasible to devise a workaround.

type Opaque<T, K extends string> = T & { __typename: K }

type Base64 = Opaque<string, "base64">

const decodeBase64 = (base64String: Base64) => {
  return Buffer.from(base64String, "base64").toString("utf8")
}

const str = "a"
decodeBase64(str) // errors

const str2 = "a" as Base64
decodeBase64(str2) // valid

One can now implement a type guard or runtime verification to confirm that a string adheres to the Base64 format for enhanced safety measures.

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

Angular tabs display the initial tab

I attempted to implement the Tabs feature from angular material by following the provided documentation. However, I encountered an issue where the first tab does not display upon page load; I have to manually click on it to view its content. For more info ...

angulartypescriptangular-material

Exporting a value from a class in Angular 2 using TypeScript

import {TranslateService, LangChangeEvent} from "@ngx-translate/core"; class CustomLanguageExporter { public currentLang : string; constructor(private translate : TranslateService) { } public static setLanguage(): string { this.tr ...

angulartypescriptangular-i18n

Template specific requirements in Angular

When I have a child component app-page-header, here's what I want to achieve: If the value of headerOptions.headerTitle is not 'Idle Disposition', then set [titleData] to equal 'headerOptions.headerTitle'. However, if headerOptions ...

angulartypescript

React Redux: Discrepancy in Variable Value Between Internal and External Function within Custom Hook

Encountering a challenge with a custom React hook utilizing Redux, where a variable's value inside and outside a function within the same hook is inconsistent. Simplified code snippet provided below: import { useAppSelector } from "Redux/helpers& ...

reactjstypescriptreduxreact-hooks

Troubleshooting webpack encore issues with importing enums from node_modules

I am faced with a challenge of utilizing an enum from a library I created in a different project. The library is developed using Vue and typescript, bundled with rollup. On the other hand, the project is built with Symfony, with the front end also using Vu ...

javascripttypescriptvue.jsenumswebpack-encore

"Encountered a problem while attempting to download the .xlsx file through http.get in an angular application interfacing

Attempting to download a .xlsx file using Angular 7 and web API in C#, encountering the following error: https://i.sstatic.net/7pwDl.png The code snippet from my service.ts is provided below: public exportExcelFile(matchedRows: string, reportInfoId: num ...

c#angulartypescriptasp.net-web-api

Leveraging default values in generic implementations

Imagine a scenario where the following code is present: type QueryResult<ResultType = string, ErrorType = string> = { result: ResultType, } | { errors: ErrorType, } So, if I want to initialize my result, I can proceed like this: const myResult: ...

typescript

When attempting to add a variable using the next() function, I encountered an error with the BehaviorSubject. The error message displayed was "this.count.next is not a function"

In my Angular service, there is a variable called count that I need to monitor for updates. Whenever this count variable is updated, I want to assign its new value to another variable in a separate component. import {BehaviorSubject} from "rxjs/BehaviorSu ...

javascriptangulartypescriptrxjs

Tips for preventing duplicate data fetching in Next.js version 13

I am currently in need of retrieving information from the database, generating metadata, and displaying the page content. The current method I am using is as follows: export const generateMetadata = async ({ params: { questionSlug }, }: Props): Promise&l ...

typescriptnext.jsnext.js13

Customized interfaces utilizing generic components

Here is my simplified question. interface Identity{ name: string; } Next, we have a generic interface. interface State<T extends Identity>{ [T.name] : StateContainer<T> } Unfortunately, this approach fails and the following error is ...

typescripttypescript-generics

TypeB should utilize InterfaceA for best practice

I have the following TypeScript code snippet. interface InterfaceA { id: string; key: string; value: string | number; } type TypeB = null; const sample: TypeB = { id: '1' }; I am looking for simple and maintainable solutions where TypeB ...

javascripttypescripttypescript-typings

I am looking for a way to transfer data collected from an input form directly to my email address without the need to open a new window. As of now, I am utilizing angular

Is there a way to send this data to my email address? I need help implementing a method to achieve this. {Name: "John", phoneNumber: "12364597"} Name: "John" phoneNumber: "12364597" __proto__: Object ...

javascriptangulartypescriptangular-cli

Angular service providing components (TypeScript error)

This is my first time trying to dynamically inject components and so far, I've been successful. However, there's an error in Typescript that's bothering me (I don't like having errors in my code). If you want to check out the app, here ...

angulartypescript

Error message: The database query function is encountering an issue where the property 'relation.referencedTable' is undefined and cannot be accessed

Currently, I am working with two schemas named products.ts and category.ts. The relationship between these files is defined as one-to-many. In the products.ts file: import { pgTable, timestamp, uuid, varchar } from "drizzle-orm/pg-core"; import ...

typescriptpostgresqlrelationshipdrizzledrizzle-orm

Connecting Angular modules via npm link is a great way to share common

Creating a project with a shared module that contains generic elements and components, such as a header, is my goal. This shared module will eventually be added as a dependency in package.json and installed through Nexus. However, during the development ph ...

angulartypescriptnpm

When utilizing typescript to develop a node module and importing it as a dependency, an issue may arise with a Duplicate identifier error (TS2300)

After creating a project called data_model with essential classes, I built a comprehensive gulpfile.js. This file not only compiles .ts to .js but also generates a unified .d.ts file named data_model.d.ts, which exports symbols and is placed at the root of ...

node.jstypescriptnode-modulestsd

Obtain abbreviated names for the days of the week starting from Monday to Sunday using JavaScript

Is there a way to retrieve the abbreviated names of each day of the week in JavaScript, starting from Monday through Sunday? ...

javascripttypescriptdatedays

Using Typescript to customize the color of Ionic's Ion-checkbox

I am attempting to modify the color of the ion-checkbox using TypeScript <ion-item > <ion-label id="check1">No</ion-label> <ion-checkbox color="blue" id="box1" [(ngModel)]="todo.check1" name="check1"></ion-checkbox&g ...

typescriptionic-frameworkcheckboxcolorsion-checkbox

Does having an excessive amount of variable declarations result in a noticeable decline in performance?

One thing I notice for the sake of readability is that I tend to create new variables for data that I already have on hand. I'm curious, does this impact performance significantly? Here's an example of what I mean: const isAdult = this.data.per ...

javascripttypescriptcode-readability

What is the capability of dynamically generating an index in Typescript?

Can you explain why the Typescript compiler successfully compiles this code snippet? type O = { name: string city: string } function returnString(s: string) { return s } let o1: O = { name: "Marc", city: "Paris", [returnString("random")]: ...

typescript